The best-selling salts in the US contain microscopic quartz (rock) substances. It's anti- caking. Many foods -- and non-foods -- also contain silicium dioxide (or its ilk) that makes some of us cough.

Try to stop using them in your cooking and eating where they serve them -- after informing them what they're doing, if they don't change. Stop buying fast foods or grocery items that contain them.

Oh well, you/ we won't/can't -- to assure us of non-contamination.

I don't consume anything I think could could contain these microscopic slivers. And still I cough sometimes. Even the good salts* can cause coughing in those sensitive or for whom "years have gone by" to quote an Ear Nose and Throat doctor.

*A good salt company list includes Diamond Crystal and Celtic Sea Salt. (The companies don't know I exist.)

Solution is a helpful solution. Until we figure out otherwise.